In typical vehicles, a spare tire housing for housing a spare tire is provided at a rear floor in a vehicle body rear part. When a vehicle having such a structure receives a load from a rear side of the vehicle, the front end of the spare tire moves toward a front side of the vehicle, so that the spare tire housing is deformed and is displaced toward the front side of the vehicle. Since, in particular, a fuel tank may be arranged forward of the spare tire housing, the deformed spare tire housing may possibly come into contact with the fuel tank. Therefore, such deformation and displacement are undesirable.
One possible countermeasure against such an event is to secure sufficient space between the spare tire housing and a back panel, so that the load can be absorbed around the spare tire housing. In addition, in the case in which the fuel tank is arranged forward of the spare tire housing, another possible countermeasure is to secure a sufficient distance between the spare tire housing and the fuel tank so that the load can be absorbed around the spare tire housing.
On the other hand, it is necessary to secure a space to arrange components other than the spare tire housing and the fuel tank. Furthermore, there are many limitations in the layout of body components. Therefore, in many cases, it is unlikely that a sufficient space can be secured behind the spare tire, that a sufficient distance can be secured between the spare tire housing and the fuel tank, etc. If sufficient space behind the spare tire housing, the sufficient distance between the spare tire housing and the fuel tank, etc., were secured, there would be a problem in that the vehicle body would increase the size of the vehicle. In particular, this problem is more serious for small vehicles.
Furthermore, when a load from the rear side of the vehicle is applied, the front end of the spare tire sometimes moves upward and forward. In this case, since rear seats are arranged at locations forward of and above the spare tire housing, the front end of the spare tire may come into contact with the rear seats, and this would be a problem.
For example, Japanese Unexamined Patent Publication No. 10-316050 discloses the following structure to avoid contact of a deformed spare tire housing with the fuel tank. A spare tire is housed within the spare tire housing in an inclined orientation so as to place a front side of the spare tire above the arrangement location of a fuel tank.
Japanese Unexamined Patent Publication No. 2006-205810 discloses the following structure to avoid contact of a deformed spare tire housing with a fuel tank and also to prevent contact of a front end of a spare tire with rear seats. In this structure, when receiving a load from a rear side of the vehicle, side frames, which are arranged on both ends, in the vehicle width direction, of a rear floor, deform respectively at locations forward of the spare tire housing in the rear floor so as to lift up the rear seats which are arranged generally above the fuel tank.
Japanese Unexamined Patent Publication No. 2009-179181 discloses the following structure. A spare tire is arranged within a spare tire housing in an inclined orientation while the front end thereof is down. When receiving a load from a rear side of the vehicle, a rear portion of the spare tire is tipped up so as to be vertically turned around the front end of the spare tire toward a front side of the vehicle. This reduces the load which is applied to a structure in front thereof on the basis of the front end of the spare tire.